I presume the static IP that you assigned to your Slingbox is not the same set of numbers as shown in the title of your message. Have you tried to log in to your router from a computer to see what devices it shows connected? If there is a device listed for that IP address in your message title that you don't recognize, perhaps that is a rogue device -- possibly something that has hacked into your local area network.
You might try cold booting your router and see if that one goes away, then assign a new static IP address to your router, making sure that it is outside the range of addresses that your router is allowed to assign dynamically. Forward port 5001 to that static IP address that you assign to your SB, then reboot both router and SB and see if it now works OK.
Report back on any messages that you get in this process.